John Dabiri has found a surprising connection between the human heart and jellyfish swimming, and it could have profound health consequences.

When engineer and biophysicist John Dabiri wants to build something efficiently, he consults a definitive source on the subject: the ocean. The 30-year-old Caltech scientist reverse-engineers marine systems to build more efficient machinery. One of his designs, a wind farm, models the dynamics of large schools of fish to generate 10 times as much power per acre of land as conventional wind farms. Last year, Dabiri won a MacArthur grant for his investigation of the similarities between the way a jellyfish swims and a human heart pumps blood—research that could lead to better ways to diagnose heart disease. We recently caught up with Dabiri.

Your career really began with an undergraduate summer fellowship at Caltech.
Right. I arrived thinking I was going to do conventional engineering research. Instead, I spent the summer making video recordings of jellyfish. It really opened my eyes to the fact that there’s a lot of interesting engineering in the natural world.

What is so fascinating to an engineer about jellyfish?
Jellyfish motion is simple but extraordinarily efficient. When they swim, they create spinning, doughnut-shaped masses of water called vortex rings, and then they push off these rings almost like a boat pushing off its own wake.

How did these rings inspire your team’s design for a research submarine?
Typical jet propulsion pushes water in a straight stream. Modulating the jet flow to create pulsing vortex rings instead lets the vehicle travel 40 percent farther on the same battery charge.

And these rings can also help diagnose heart disease?
Yes. A healthy human heart creates similar vortex rings in the blood. When a heart starts to fail, the rings become muddled, resembling those of panicking jellyfish. This gives us a potential index to detect heart failure at early stages.

Jellyfish are hardly cuddly. Have you ever been stung? I was doing a photo shoot a couple of years ago where the photographer had me in the water holding a jellyfish with gloves, but its tentacles broke off all around me and got into my board shorts. That was pretty horribly painful.